Signaling transmitter



Sept. 27, 1932. M. HANLEY 1,879,934

S IGNALIN G TRANSMITTER Original Filed Dec. 29, 1928 2 Sheets-Sheet 1 S IGNALING TRANSMITTER Original Filed Dec. 29, 1928 2 Sheets-Sheet 2 Patented Sept. 27, 1932 UNITED STATES MICHAEL HANLEY, OF CHICAGO, ILLINOIS SIGNALING TRANSMITTER Original application filed December 29, 1928, Serial No. 329,175. Divided and this application filed May 7, 1930. Serial No. 450,382.

This invention relates to signaling transmitters and more particularly to such transmitters as are employed in fire alarm and police box systems of the type disclosed in my copending application, Serial No. 329,175, filed December 29, 1928, for signaling system, of which this application is a division.

The preferred form of firealarm and police box systems employ a single wire circuit extending outward from a central office through a plurality of alarm boxes and thence back to the central oifice. A relay and a source of electro-motive force are included in this circuit in the central office, that relay being normally maintained energized over the closed line circuit through the boxes. lVhen a box is pulled to turn in a report or an alarm, the line circuit is inv terrupted by the mechanism in the box a plurality of times to transmit a code to the central ofiice indicating the designation of the box which was pulled.

Each interruption of the line circuit opens the circuit of the central oflice relay, permitting it to fall back during the period that the line circuit is open. The deenergization of the line circuit relay operates a printing recorder or a telegraph sounder, or both, to apprise the central oflice attendants of the operation of the box.

In the orthodox system of this kind, the breaking of a line wire or the short circuiting of the line circuit or part of the line circuitputs the circuit or the shorted part of it out of commission, until such trouble can be repaired.

In my above mentioned copending appli cation, I have modified the circuits and the equipment of such orthodox systems by providing an additional relay at the central office which is normally deenergized, that is, adapted to work on a so-called open circuit. I have also provided additional contacts at the pull boxes which under certain conditions will apply ground to the line circuit. This ground completes a circuit through the open circuitrelay to operate that relay to register the code being transmitted at the time. The closed circuit relay of the usual orthodox system functions in the same manner as in the circuit that has been in use heretofore. These modifications add reliability to the system by permitting the transmission of signals over the circuit when that circuit contains a combination of faults. With the improved circuit disclosed therein, I am able to transmit signalssatisfactorily, even though the line be open, grounded, open and grounded, or a loop portion of it be short circuited, or with various combinations of such faults. In fact with my new system, a box remains in service until the line leading to and from it is broken or grounded on both sides of the box, and even under these conditions only that particular box is lost from service.

The preferred form of pull box mechanism now in common use in systems of this kind such as the so called Chicago standard'box transmits the code indicative of that particular box four times each time the box is pulled. In my present application, I have modified a standard box of this kind and have adapted the circuit of the box so that'two of these four rounds transmit signals over an open wire circuit extending from the ground at'the box and two rounds transmit signals by the usual interruption of the loop circuit.

In my present invention, I provide the central office with suitable keys and circuits which arrange the equipment so that one or the other of the line relays will receive a signal transmitter from the box, even though any one of a large variety of combinations of faults exist upon the line circuit.

In the drawings, I have shown sufficient apparatus and details to enable one skilled in the art to acquaint himself with the preferred form of my invention.

In the drawings:

V Figure 1 shows by the usual symbols the circuit involved in the preferred embodiment of my invention;

Figure 2 is'a plan view of the pull box mechanism showing the spring assemblies, cams, and levers employed to control the circuits of the preferred embodiment of my invention; and

Figure 3 is a plan view of a pull box mechanism, showing a modified form of the spring assembly, which may be employed in the circuit shown in Figure 1. Referring to Figure 1, now, more in detail, I show at the left of the dotted line that equipment which is located in the central mice, and to the right of the dotted line show a line circuit including the pull boxes 30 to 36, inclusive, with the box 34, shown in detail. It is to be understood that the line circuit is not shown in full and that many more boxes may be added to it, if desired.

The equipment at the central oflice comprises the closed circuit relay 1, which in the normal operation of the system is maintained energized by current from the battery 20flowing through the relay and the normally closed line circuit. The circuit through the line, battery and relay 1 is controlled by the switch 8, which is normally thrown in the position shown in the drawings. 'fWith the relay in its energizedposition, the circuit through its contacts 17 18 and 19 is arranged by the key 7, so that the circuit of the printing recorder 3 is closed by the contacts 17 and 19, when the relay is deenergized.

The central ofi ice equipment also comprises the open circuit relay 2, which is normally deenergized and is energized only when a box on the line is pulled. Pulling of the box closes a circuit from ground at the box through the battery 21, the relay 2, the switch 5, pilot lamp 10, and the resistance 11, to ground. The contacts 14, 15, and 16, controlled by the relay 2, are arranged by the key 6, so that contacts 14 and 16 close the circuit of the printing recorder 3, when the relay 2 is energized.

The printing recorder 3 may be anypre- :terred type of telegraph recorder or pen register adapted to make a printed record of series of impulses delivered to its operating magnet. I l

The key 9 normally connects the printing recorder 3 to the circuits controlled by the contactsof the relays 1 and 2, the key being operated to disconnect the recorder 3 and to substitute the signal4 in this circuit. The signal 4may be a telegraph sounder, a bell, buzzer or any preferred form of audible signal.

I Referring, now, to the circuit details of the pull box 34, itwill be noted that the line circuit normally extends through the box, that circuit including the segment controlled switch 61. When the box is pulled, the

switch '61 is opened and the circuitf'maintained closed through the springs 44, 46 and 45, those springs being incorporated in the assembly controlled by the code wheel 40.

When the box is pulled, the lever 50 moves to the right, out of engagement with the cam 51, and the spring tension of springs 53 and 54 move the cam upward by applying tension to the bushings 52. This closes contacts 56, 53 and 57, and contacts 54 and 55. Contacts 54 and 55 are connected in multiple with the contacts 44, 45 and 46, so that the line circuit is maintained complete through the call box, independent of the action of the code wheel, as long as the lever 50 is out of engagement with the cam 51 and the spring set controlled thereby is closed.

The operation of the cam 51 closes the springs 53, 56, and 57, extending a circuit from ground to the springs 42 and 43 of the code wheel spring set. By this arrangement, when the bushing 41 rides over a tooth on the code wheel 40 and presses springs 42, 43 and 46 downward, a circuit is closedfrom ground through the springs 42 and 43, throughthe springs 44 and 45, respectively, to thereby momentarily apply ground to the line circuit. The operation of spring 46 opens contacts 44 and45, but this operation is without effect, at this time, because those con tacts are shunted by the contacts 54 and 55 of the cam spring assembly.

By referring to Figure 2, it will be seen that I have attached the lever 50 to the shaft which carries the segment 102 of the pull box mechanism. l/Vhen the box is pulled, a lever projecting through the box casing is moved downward to move the lever 100 in a counterclockwise direction. This moves the segment 102 downward, tensions the" spring 101 and moves the lever 50 to the right. v

The operation of the segment 102 to its lowermost position does not move the code wheel 40. When the lever attached to lever 100 is released, the tension put in the spring 101 moves the segment upward. The speed at which the segment moves upward is controlled by the clockwork mechanism and governor, and the code wheel 40 is rotated in a counter-clockwise direction, as shown by the arrow. During the movement of the segment 102 from its lowermost to its uppermost position, the code Wheel 40 makes four complete revolutions.

The lever 50 is arranged on the shaft of the segment, so'that it is out of engagement with the cam 51, during the first two of the four revolutions of thecode wheel 40. That is, the springs 53 to 57 inclusive, controlled by the cam 51 and lever 50 are closed only during the first two revolutions of the code wheel. The code wheel transmits a code of impulses indicative of the designation of the pull box, each time it makes a complete revo-v lution. By this arrangement, which is standard practice in systems of this kind, the code indicating the box is transmitted four times, each time the box is pulled.

Referring, now, to Figure 1, again, it will be notedthat when the code wheel 40 makes the first'two ofits four revolutions, responsive to the pulling of the box, the code is transmitted by impulses of ground placed on the line through springs 53, 56, 57 42, 44, and 43, 45 and that the openingof the line circuit by springs '46 is nullified by springs 54 and 55.

During the last two revolutions of the code wheel, the lever 50 is again in engagement with the cam 51, and springs 53 to 57, inclusive, are opened by the downward move ment of the cam 51 and bushing 52. This removes the ground connection from the line, and makes the interrupting of the line circuit by the springs 44, 45 and 46 efiective to control the relay 1 at the central oflice. Thus, it will be seen that, in the normal operation of the system disclosed in Figure 1, the code signal is transmitted by the pulling of the box, first by impulses of ground over the line, and second by interruption of the normally closed series line circuit.

l/Vhen the bushing 41 is moved downward over a tooth of the code wheel 40, during the first two revolutions of the code wheel, a circuit is closed from ground 60 through spring 53 and spring 56, springs 42 and 44, to the line circuit extending from the box 34 through boxes 30 to 33, inclusive, through the winding of the relay 1 and the battery 20, the switch 8, battery 21, relay 2, switch 5, lamp 10, resistance 11, to ground. A parallel circuit is closed from ground 60 through springs 53 and 57, springs 43 and 45, through the line extending to the right of the box 34, through the boxes 35 and 36, through the battery 21, the relay 2, the key 5, lamp 10, and resistance 11, to ground. If the line circuit is broken to the left of the box 34, the first of these parallel circuits will not be closed, but the second will be closed and the relay 2 will be energized thereover. Conversely, if the line is broken to the right of the box 34, the second circuit will not be closed, but the first one will and the relay will be operated thereover. The pilot lamp 10 lights over this circuit to ap prise the dispatcher that the signal then being received is coming in over the open circuit relay. The resistance 11 is included in the circuit to limit the current flowing through the lamp and relay, so that current will not be excessive when a box close to the o'lfice is pulled.

The energization of relay 2 closes a circuit through springs 14 and 16, the key 6, battery 13, left hand contacts of key 9, the printing recorder 3, right hand contacts of key 9, back to the spring 14, energizing the magnet of the recorder 3. The relay 2 falls back when the bushing 41 drops over the tooth of the code wheel 40 and opens the springs 42 and 43, to open at springs 14 and 16 the circuit of the printing recorder to terminate the impulse recorded thereby. This circuit is closed a number of times, depending upon the number of teeth in the particular box 34, that number of teeth being varied with each box on the line, to cause it to transmit a code individual tothe box. In this manner, the first two rounds of the code wheel 40 are recorded by the recorder 3 under the control of .relay 2.

During the last two rounds of the code wheel 40, the shunt around springs 45 and 46 is removed by the action of the cam 51 and the ground connection is removed from the springs 42 and 43, by the same action. The normally closed circuit through the relay 1 is, therefore, interrupted by the springs 44, 45, and 46, to permit that relay to fall back each time the bushing 41 rides over a tooth on the code wheel. The deenergization of the relay 1 closes a circuit from the battery 13 through the key 7, spring 17 and 19, through the right hand contacts of the key 9, through the printing recorder, through the left hand contacts of the key 9 to the battery 13.

The impulses sent out by the code wheel are, therefore, recorded on the recorder under the control of the contacts of the relay 1, this record being repeated twice as the code wheel makes its last two revolutions.

If the line circuit should become grounded at a single point located on the right hand side of the box 34, as at B, relay 1 will receive directground on one of its terminals through boxes 3034. The battery 20 will be directly grounded through the switch 8 and boxes 36 and 35 by the ground at B. Under these circumstances the operation of the code wheel 40 will still open the circuit of the relay 1, permitting the transmission of a closed loop signal from the box. 34. Boxes 3033 located between box 34 and relay 1 are likewise capable of'transmitting signals under these conditions. Boxes 35 and 36, and others which are located in the line between B and the relay 2 are virtually short circuited' by the ground at B and incapable of transmitting signals. When the line circuit springs of box 36, for example, open the circuit of relay 2, which extends from ground through resistance 11, lamp 10, switch 5, relay 2, battery 21, to ground at B, relay 2 does not fall back, since it receives currentover a parallel circuit traceable from ground through resistance 11, lamp 10, switch 5, relay 2, battery 21, switch 8, battery 20, relay 1, and boxes 30--34 to ground at B. Relay 2 becomes permanently energized from the ground at B over these parallel circuits and causes the recorder 3 to be operated continuously, thereby attracting attention to the fault. throws key 6 into its alternate position to convert relay 2 from an open circuit relay into a closed circuit relay, and throws key 8 into its alternate position to convert the system into two separate lines, both operating closed circuit relays at the central station. Line 1 extends from ground, through the resistance 12, key 8, battery 20, relay 1 and boxes 3034 inclusive to ground at the fault B, and line 2 extends from ground through resistance 11, lamp 10, switch 5, relay 2, battery 21, and boxes 3536, to ground at fault B. Both The attendant then lines are capable of transmitting signals during two of their four revolutions when'pulled, and all of the boxes on the lines are in service. A ground at some other point on the main line instead of at B acts to transfer boxes from line 1 to'line 2 and vice versa, the operation of course being as above described.

It the line circuit is broken, the relay 1 falls back and remains back permanently and, of course, the transmission of signals by it is impossible until the central oliice equipment is rearranged by an operation of the keys 6, 7 or 8. y 7

Assume that the line breaks at the point AB between the pull box 3A and the pull box 35. The relay 1 will fall back, permanently closing the circuit to the printing recorder to cause that recorder to run continuously, to thereby attract the central station attenda-nts attention to the trouble. The attendant will then throw the key '7 to its opposite position, changing relay 1 from a closed circuit relay to an open circuit relay by altering the circuit through the springs controlled by the relay. vVith the break at this point, the box 3A will still transmit a signal during the first two rounds of the code wheel over a circuit from ground in the box itself, through the previously traced circuit through the box to the line extending through the boxes 30 to 33, inclusive, through the relay 1 and the battery 20, the key 8, battery 21 and the relay 2, thence over the previously traced circuit to ground.

Both relays 1 and 2 can be operated by the impulses, as open circuit relays to operate the register to record the signal transmitted by the box 34.

Assuming that the break between boxes 34 and 35 grounds the line on the end or the break adjacent to the box 34, as shown at B in Figure 1, with the opposite end of the break open and clear, as shown at A, the relay 1Will be energized as before over a circuit from ground at B, through boxes 30-3 1, relay 1, battery 20, key 8, battery 21, relay 2, key 5, lamp 10, resistance 11, to ground. The relay 2 will also be energized over this circuit, and since the controlling key 6 of this relay is set to makeit an open circuit relay, its energization will cause the recorder 3 to run continuously and thereby attract the attendants attention. The central ofiice attendant will then operate key 6 to change i relay 2 from an open circuit relay to a closed circuit relay.

This leaves the recorder under the control of'relays 1 and 2 both operating as closed circuit relays, and also leaves boxes 35 ant 36 out of service. This condition necessitates splitting the line into two sections, one an open circuit line and the other a closed circuit line, so that all of the boxes will be in the service. This splitting of the line is accomplished by an operation of key 8. The

operation of key 8 against its uppermost contact will complete a circuit from ground through resistance 12 and the key 8, through the battery 20 and the. relay 1, out over the line through boxes 30 to 34, inclusive, to ground at the point of trouble B. The resistance 12 in this circuit aids in limiting the current to a value consistent with the safe operation of the system; This reconverts the relay 1 to a closed circuit relay, so that the key 7 is retained in the position shown in the drawings, and the system'is then in readiness for operation. The operation of key 8 causes relay 2 to be deenergized and switch 6 is therefore restored to the position shown in the drawings, to render relay 2 an open circuit relay again. 'The system is now set with the line circuit split so that boxes 3034': are on a closed circuit line terminating at B, and boxes 35 and 36 are on an open circuit line terminating at A. Boxes 30 to 34 will transmit no signals during the first two revolutions of their respective code wheels, due to the grounded condition of the line through them. The same boxes will transmit two codes during the last two rounds of their respective code wheels, opening the closed circuit of the relay 1 in the usual manner.

Signals from boxes 35 and 36 and the other boxes on that side of the line which remains clear will transmit signals during the first two revolutions of their respective code wheels and will not transmit signals during the last two revolutions of the code wheel.

If the break at the point AB grounds on both sides of the break, that is, at point A and B, relay 2 becomes energized permanently and the recorder is run continuously by the circuit closed through the contacts 14, 15. The pilot lamp 1O burns, also, to indicate to the attendant that the circuit through relay 2 is completed. The attendant then throws the key 6 in an upward direction, converting the relay'2 from an open circuit relay to a closed circuit relay, and reports are received from boxes 35 and 36 over a closed circuit extending from ground at the point of trouble A to ground at the central office through relay 2. The switch 8 is also operated as above explained and the line is then operating as two lines, each extending from ground at the central oflice to ground at the point of trouble. I

Boxes 32 and 33 are represented as being upon a loop in the main line. If this loop should become shorted, as indicated at 0, boxes 32 and 33 would transmit code signals during thefirst two revolutions of their respective code wheels. The other boxes on the system would operate in the normal manner, that is, transmit two codes of grounded impulses and two codes of closed circuit impulses. If the loop is grounded as Well as shorted at C, boxes 32 and 33 are thrown out newest:

of service, but the remainder of the boxes can be made to operate during the last two rounds over a closed circuit. The key 8 is again operated to split the line into two sections, in this case boxes 30 and 81 being on one section with the relay 1 and boxes 34-86 on the other section with the relay 2.

From the foregoing description, it is apparent that the circuits shown in Figure 1 are flexible enough to permit the receiving of signals at the central office even though the line be faulty, by reason of a combination of troubles. Taking the box 34, for example, the only condition that completely puts this box out of service is the breaking of the line at both sides of the box, or the grounding of the line at both sides of the box, as for example, at points B and C. Even with this peculiar combination of troubles, the box 34 is the only box on the system that is out of service.

In Figure 3, I have shown a modified arrangement of the pull box mechanism. Instead of providing the segment shaft with the lever 50, as in the preferred form shown in Figure 2, I have placed the insulating bushing 103 at the lowermost section of the segment 102. Disposed around the periphery of the housing of the mechanism are the springs 53, 56, 57, 54 and 55, which springs 53 and 54 lie in such a position as to be engaged by the bushing 103, when the segment is in its lowermost position. This operates the springs over against their associated springs to close the contacts as before, contacts 54- and 55 being in multiple with the contacts 44 and 45, as before, and contacts 53, 56 and 57 placing ground upon contacts 42 and 43, as before. The bushing 103 engages the springs during the first two rounds of the code wheel 40, and moves away from them at the completion of the second round, as before. The circuits and operation of the system are the same as before, and need not be repeated in detail at this time.

While I have shown the keys 6, 'Z, 8 and 9 as a particular type of key, obviously any suitable switch or key may be substituted for the type shown. Also, I am not to be limited by the specific details of the circuit and pull box mechanisms shown, as these arrangements may be modified greatly without departing from the teachings of my invention.

Having thus complied with the statutes and shown and described a preferred embodiment of my invention, what I consider new and desire to have protected by Letters Patent is pointed out in the appended claims.

I claim:

1. In combination with an alarm box having a code wheel operated by a clockwork driven by a segment and spring when the box is pulled, normally closed springs momentarily opened by said code wheel, normally opened springs operated by said code wheel to momentarily make contact with certain of said normally closed springs, a normally opened spring set, means moved with said segment to close said latter spring set during a part of the cycle of operation of the code wheel, circuit connections for connecting certain of said latter springs to said normally opened code wheel springs and to connect other of said latter springs in multiple with said normally closed code wheel springs, and a circuit through said box controlled jointly by said springs responsive to an operation of said segment and code wheel.

2. In combination with an alarm box having a code wheel operated by a clockwork driven by a segment and spring when the box is pulled, a line circuit through said box, normally closed contacts in said line circuit mo-' mentarily opened by said code wheel, normally opened springs operated by said code wheel to momentarily make contact with said normally closed springs, means moved with the segment for shunting said normally closed contacts during a portion of the movement of said segment out of its normal position, a ground connection to said box normally isolated from said code wheel operated springs, and means controlled by said first means for extending said connection to said normally opened code wheel contacts during said portion of the movement of said segment.

8. An alarm box comprising the combination of a code wheel, driving means therefor operated to drive the code wheel through four revolutions each time the box is pulled, a normally closed circuit through said box including springs momentarily opened by said code wheel, a normally opencircuit in said box including springs momentarily closed by said code wheel, a set of normally open springs, means for closing sa-idnormally open springs during two revolutions of the code wheel, circuit connections between said code wheel springs and segment controlled springs over which said segment controlled.

springs when closed shunt'the springs of said normally closed circuit and close a point in said normally open circuit.

4. Incombination with an alarm box having a code wheel therein, means for driving said code wheel through a plurality of revoloo tions of the code wheel to close said normally open springs.

5. In combination with an alarm box havinga code wheel therein, means for driving 4 said code wheel when the box ispulled, normally closed springs momentarily opened by said code wheel, normally opened springsoperated by said code wheel to momentarily make contact with certain of said normally closed springs when the latter are opened, a

normally opened spring set, means moved with said driving means to close said latter spring set during but a part of the operation of said driving means, and circuit con- -nections for connecting certain of said latter springs to said normally opened code wheel springs and to connect other of said latter springs in multiple with said normally closed code wheel springs. s

6..An alarm box comprising the combination of a code wheel, driving means thereforoperated to drive the code wheel through four revolutions each time the boxis pulled, a normally closed circuit through said box including contacts momentarily opened by said code wheel, a normally open circuit in said box including contacts momentarily closed by said code wheel, aset of normally open contacts, means including a cam and lever for closing said contacts during two revolutions of the code wheel, and circuit connections between said code wheel contacts and normally open contacts over which the latter when closed shunt the contacts of said normally closed circuit and close a point in said normally open circuit.

7. An alarm box comprising the combination of a code wheel operated by a clockwork driven by a segment and spring when the box is pulled, a normally closed i circuit through said box including springs momentarily opened by said code wheel, a normally open circuit in said box including springs momentarily closed by said code wheel, a set of normally open springs, segment controlled means for closing said normally open springs during a part of the movement of the segment, circuit connections between said code wheel springs and segment controlled springs over which said segment controlled springs when closed shunt the springs of said normally closed circuit and close a point in said normally open circuit.

In witness thereof, I hereunto subscribe my name this 5th day of May, 1930.

MICHAEL HANLEY. 

